Do not warn about non-translated strings in the ant library

Ant tasks are generally not translated, hence don't warn about
untranslated strings

Change-Id: I60920ccdaf3c0139979bb4ef19eb42036bb7e07f

org.eclipse.jgit.ant/.settings/org.eclipse.jdt.core.prefs

@@ -60,7 +60,7 @@ org.eclipse.jdt.core.compiler.problem.missingSerialVersion=warning
 org.eclipse.jdt.core.compiler.problem.missingSynchronizedOnInheritedMethod=ignore
 org.eclipse.jdt.core.compiler.problem.noEffectAssignment=error
 org.eclipse.jdt.core.compiler.problem.noImplicitStringConversion=error
-org.eclipse.jdt.core.compiler.problem.nonExternalizedStringLiteral=warning
+org.eclipse.jdt.core.compiler.problem.nonExternalizedStringLiteral=ignore
 org.eclipse.jdt.core.compiler.problem.nullAnnotationInferenceConflict=error
 org.eclipse.jdt.core.compiler.problem.nullReference=error
 org.eclipse.jdt.core.compiler.problem.nullSpecViolation=error